Devices and methods for heart valve treatment

ABSTRACT

Devices and methods for treating heart valves include members that assist the valve in closing during at least a portion of the cardiac cycle. Such devices include members configured to alter the shape of a valve annulus, reposition at least one papillary muscle, and/or plug an orifice of the valve so as to provide a coaptation surface for the valve leaflets.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of application Ser. No. 10/866,990,filed on June 15, 2004, now U.S. Pat. No. 7,077,862, which is acontinuation of application Ser. No. 10/040,784, filed on January 9,2002, now U.S. Pat. No. 6,764,510, both of which are incorporated hereinby reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to devices and related methods fortreating and improving the function of dysfunctional heart valves. Moreparticularly, the invention relates to devices and related methods thatpassively assist to close a heart valve to improve valve function ofpoorly functioning valves.

2. Description of the Related Art

Various etiologies may result in heart valve insufficiency dependingupon both the particular valve as well as the underlying disease stateof the patient. For instance, a congenital defect may be presentresulting in poor coaptation of the valve leaflets, such as in the caseof a monocusp aortic valve, for example. Valve insufficiency also mayresult from an infection, such as rheumatic fever, for example, whichmay cause a degradation of the valve leaflets. Functional regurgitationalso may be present. In such cases, the valve components may be normalpathologically, yet may be unable to function properly due to changes inthe surrounding environment. Examples of such changes include geometricalterations of one or more heart chambers and/or decreases in myocardialcontractility. In any case, the resultant volume overload that exists asa result of an insufficient valve may increase chamber wall stress. Suchan increase in stress may eventually result in a dilatory process thatfurther exacerbates valve dysfunction and degrades cardiac efficiency.

Mitral valve regurgitation often may be driven by the functional changesdescribed above. Alterations in the geometric relationship betweenvalvular components may occur for numerous reasons, including eventsranging from focal myocardial infarction to global ischemia of themyocardial tissue. Idiopathic dilated cardiomyopathy also may drive theevolution of functional mitral regurgitation. These disease states oftenlead to dilatation of the left ventricle. Such dilatation may causepapillary muscle displacement and/or dilatation of the valve annulus. Asthe papillary muscles move away from the valve annulus, the chordaeconnecting the muscles to the leaflets may become tethered. Suchtethering may restrict the leaflets from closing together, eithersymmetrically or asymmetrically, depending on the relative degree ofdisplacement between the papillary muscles. Moreover, as the annulusdilates in response to chamber enlargement and increased wall stress,increases in annular area and changes in annular shape may increase thedegree of valve insufficiency. Annular dilatation is typicallyconcentrated on the posterior aspect, since this aspect is directlyassociated with the expanding left ventricular free wall and notdirectly attached to the fibrous skeleton of the heart. Annulardilatation also may result in a flattening of the valve annulus from itsnormal saddle shape.

Alterations in functional capacity also may cause valve insufficiency.In a normally functioning heart, the mitral valve annulus contractsduring systole to assist in leaflet coaptation. Reductions in annularcontractility commonly observed in ischemic or idiopathic cardiomyopathypatients therefore hamper the closure of the valve. Further, in a normalheart, the papillary muscles contract during the heart cycle to assistin maintaining proper valve function. Reductions in or failure of thepapillary muscle function also may contribute to valve regurgitation.This may be caused by infarction at or near the papillary muscle,ischemia, or other causes, such as idiopathic dilated cardiomyopathy,for example.

The degree of valve regurgitation may vary, especially in the case offunctional insufficiency. In earlier stages of the disease, the valvemay be able to compensate for geometric and/or functional changes in aresting state. However, under higher loading resulting from an increasein output requirement, the valve may become incompetent. Suchincompetence may only appear during intense exercise, or alternativelymay be induced by far less of an exertion, such as walking up a flightof stairs, for example.

Conventional techniques for managing mitral valve dysfunction includeeither surgical repair or replacement of the valve or medical managementof the patient. Medical management typically applies only to earlystages of mitral valve dysfunction, during which levels of regurgitationare relatively low. Such medical management tends to focus on volumereductions, such as diuresis, for example, or afterload reducers, suchas vasodilators, for example.

Early attempts to surgically treat mitral valve dysfunction focused onreplacement technologies. In many of these cases, the importance ofpreserving the native subvalvular apparatus was not fully appreciatedand many patients often acquired ventricular dysfunction or failurefollowing the surgery. Though later experience was more successful,significant limitations to valve replacement still exist. For instance,in the case of mechanical prostheses, lifelong therapy with powerfulanticoagulants may be required to mitigate the thromboembolic potentialof these devices. In the case of biologically derived devices, inparticular those used as mitral valve replacements, the long-termdurability may be limited. Mineralization induced valve failure iscommon within ten years, even in older patients. Thus, the use of suchdevices in younger patient groups is impractical.

Another commonly employed repair technique involves the use ofannuloplasty rings. These rings originally were used to stabilize acomplex valve repair. Now, they are more often used alone to improvemitral valve function. An annuloplasty ring has a diameter that is lessthan the diameter of the enlarged valve annulus. The ring is placed inthe valve annulus and the tissue of the annulus sewn or otherwisesecured to the ring. This causes a reduction in the annularcircumference and an increase in the leaflet coaptation area. Suchrings, however, generally flatten the natural saddle shape of the valveand hinder the natural contractility of the valve annulus. This may betrue even when the rings have relatively high flexibility.

To further reduce the limitations of the therapies described above,purely surgical techniques for treating valve dysfunction have evolved.Among these surgical techniques is the Alfiere stitch or so-calledbowtie repair. In this surgery, a suture is placed substantiallycentrally across the valve orifice between the posterior and anteriorleaflets to create leaflet apposition. Another surgical techniqueincludes plication of the posterior annular space to reduce thecross-sectional area of the valve annulus. A limitation of each of thesetechniques is that they typically require opening the heart to gaindirect access to the valve and the valve annulus. This generallynecessitates the use of cardiopulmonary bypass, which may introduceadditional morbidity and mortality to the surgical procedures.Additionally, for each of these procedures, it is very difficult, if notimpossible, to evaluate the efficacy of the repair prior to theconclusion of the operation.

Due to these drawbacks, devising effective techniques that could improvevalve function without the need for cardiopulmonary bypass and withoutrequiring major remodeling of the valve may be advantageous. Inparticular, passive techniques to change the shape of the heart chamberand associated valve and/or reduce regurgitation while maintainingsubstantially normal leaflet motion may be desirable. Further,advantages may be obtained by a technique that reduces the overall timea patient is in surgery and under the influence of anesthesia. It alsomay be desirable to provide a technique for treating valve insufficiencythat reduces the risk of bleeding associated with anticoagulationrequirements of cardiopulmonary bypass. In addition, a technique thatcan be employed on a beating heart would allow the practitioner anopportunity to assess the efficacy of the treatment and potentiallyaddress any inadequacies without the need for additional bypass support.

SUMMARY OF THE INVENTION

A recently developed passive technique that addresses at least some ofthe drawbacks discussed above includes applying passive devices to theheart, for example the left ventricle, to change the shape of theventricle and concomitantly to improve coaptation of the mitral valveleaflets. In one embodiment, the technique involves implanting splintsacross the left ventricle. Examples of various splinting approaches aredisclosed in U.S. application Ser. No. 09/680,435, filed Oct. 6, 2000,entitled “Methods and Devices for the Improvement of Mitral ValveFunction,” which is assigned to the same assignee as the presentapplication and which is incorporated by reference in its entiretyherein.

The devices and related methods which will be disclosed herein alsooperate passively to treat valve insufficiency, by altering the shape ofthe valve annulus and/or repositioning the papillary muscles, forexample. Some of the devices of the present invention may be used incombination with the splinting treatments disclosed in U.S. applicationSer. No. 09/680,435, incorporated by reference herein.

It should be understood that the invention disclosed herein could bepracticed without performing one or more of the objects and/oradvantages described above. Other aspects will become apparent from thedetailed description which follows. As embodied and broadly describedherein, the invention includes a method for treating a heart valvecomprising providing a device having an arcuate portion and at least oneelongate portion configured to extend from the arcuate portion. Themethod may further comprise encircling at least a portion of an annulusof a heart valve with the arcuate portion and adjusting a size of atleast one of the arcuate portion and the elongate portion so as to altera shape of the portion of the annulus. The method also may includesecuring the at least one elongate portion to an exterior surface of theheart.

According to another aspect, a method of treating a heart valvecomprises providing a device having an arcuate portion and at least oneelongate member configured to extend from the arcuate portion. Themethod further comprises placing the arcuate portion proximate anannulus of a heart valve and extending the at least one elongate memberfrom the arcuate portion. The method also may comprise securing the atleast one elongate member to an exterior surface of the heart, whereinthe at least one elongate member extends from the arcuate portion to theheart wall in substantially the same plane as the arcuate portion.

Yet another aspect includes a device for treating a heart valvecomprising an arcuate portion configured to at least partly encircle anannulus of the heart valve and at least one elongate portion extendingfrom the arcuate portion and configured to be secured to an exteriorsurface of a heart wall surrounding a heart chamber associated with thevalve. At least one of the arcuate portion and the elongate portion isconfigured to be adjusted in size so as to alter a shape of at least aportion of the annulus.

In yet another aspect, a device for treating a heart valve comprises anarcuate portion configured to be positioned proximate an annulus of theheart valve and at least one elongate member extending from the arcuateportion and configured to be secured to an exterior surface of the heartwall. The at least one elongate member extends from the arcuate portionto the heart wall in substantially the same plane as the arcuateportion.

According to yet another aspect, the invention includes a device fortreating a heart valve comprising at least one substantially elongatemember configured to be implanted in a lumen of a coronary vessel so asto encircle at least a portion of an annulus of the heart valve andalter a shape of at least the portion of the annulus. The device mayfurther comprise a shape change element associated with the elongatemember and configured to impart a local shape change to a portion of thevalve annulus at a location corresponding to the shape change element.

Yet another aspect includes a device for treating a heart valvecomprising at least one substantially elongate member configured to beimplanted in a lumen of a coronary vessel so as to encircle at least aportion of an annulus of the heart valve and alter a shape of at leastthe portion of the valve annulus. The shape of at least a portion of theelongate member may be configured to be adjustable so as to impart alocal shape change to a portion of the valve annulus at a locationcorresponding to at least the adjustable portion.

Yet another aspect of the invention includes a method for treating aheart valve comprising providing at least one substantially elongatemember and extending at least a portion of the elongate member within aheart wall surrounding a chamber of the heart associated with the heartvalve so as to encircle at least a portion of the heart chamber. Themethod may further comprise securing the elongate member in place withrespect to the heart and compressing at least a portion of a heart wallsurrounding at least the portion of the heart chamber so as to moveleaflets of the valve toward each other so as to assist the valve inclosing during at least a portion of the cardiac cycle.

In yet another aspect, a method for treating a heart valve comprisesproviding at least one substantially elongate member and extending atleast a portion of the elongate member within a lumen of a coronarysinus so as to encircle at least a portion of a heart chamber. Themethod further comprises securing the elongate member in place withrespect to the heart via securement mechanisms and compressing at leasta portion of a heart wall surrounding the portion of the heart chamberso as to move leaflets of the valve toward each other so as to assistthe valve in closing during at least a portion of the cardiac cycle.

Yet another aspect of the invention includes a device for treating aheart valve comprising an elongate member having first and secondoppositely disposed ends, with the elongate member being relativelyrigid, a first anchoring member configured to be attached to the firstend of the elongate member, and a second anchoring member configured tobe attached to the second end of the elongate member. The firstanchoring member may be configured to engage a first exterior surface ofa wall of the heart and the second anchoring member may be configured toengage a second exterior surface of the wall of the heart to maintain aposition of the elongate member transverse a heart chamber associatedwith the valve and substantially along a line of coaptation of thevalve. The length of the elongate member may be such that the elongatemember is capable of maintaining a substantially normal distance betweentrigones of the valve.

In yet another aspect, a method for treating a heart valve comprisesproviding a relatively rigid elongate member having first and secondoppositely disposed ends, securing the first end of the elongate memberto a first exterior heart wall surface, and securing the second end ofthe elongate member to a second exterior heart wall surface, the secondexterior surface being located substantially opposite to the firstexterior surface such that the elongate member extends substantiallytransverse a heart chamber associated with the valve and substantiallyalong a line of coaptation of the valve. The method also may comprisemaintaining a substantially normal distance between the trigones of thevalve via the elongate member.

Yet another aspect of the invention includes a device for treatingleakage of a heart valve comprising an expandable plug member having anexternal surface, with at least a portion of the plug member beingconfigured to be positioned proximate leaflets of the heart valve. Thedevice also may comprise a securement mechanism attached to the plugmember and configured to secure the plug member with respect to theheart such that during at least a portion of the cardiac cycle, theleaflets abut the external surface of the plug member to restrictbloodflow through the valve.

According to another aspect, a device for treating leakage of a heartvalve comprises a plug member having a piston-like configuration and anexternal surface being configured to abut free ends of leaflets of thevalve to restrict bloodflow through the valve during at least theportion of the cardiac cycle. The device may further comprise asecurement mechanism attached to the plug member and configured tosecure the plug member with respect to the heart.

Yet another aspect of the invention includes a method of preventingleakage in a heart valve comprising providing an expandable plug memberhaving an external surface, delivering the plug member to a heartchamber containing a valve, and positioning the plug member proximateleaflets of the valve such that the leaflets contact the externalsurface of the plug member during at least a portion of the cardiaccycle so as to restrict bloodflow through the valve.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute apart of this specification, illustrate several embodiments of theinvention and together with the description, serve to explain certainprinciples. In the drawings,

FIG. 1 a is a short-axis cross-sectional view of the heart;

FIG. 1 b is a partial short axis cross-sectional view of the heart;

FIG. 2 a is a top view of a properly functioning mitral valve in an openposition;

FIG. 2 b is a top view of a properly functioning mitral valve in aclosed position;

FIG. 2 c is a top view of an improperly functioning mitral valve in a“closed” position;

FIG. 3 a is a side view of a properly functioning mitral valve shownwith its connection to the papillary muscles;

FIG. 3 b is a side view of an improperly functioning mitral valve shownwith its connection to the papillary muscles;

FIG. 4 a is a cross-sectional view of a mitral valve and a coronarysinus with an exemplary embodiment of a curved frame member implanted inthe coronary sinus according to an aspect of the invention;

FIG. 4 b is a cross-sectional view of another exemplary embodiment of acurved frame member implanted in a coronary sinus according to an aspectof the invention;

FIG. 4 c is a perspective view of yet another exemplary embodiment of acurved frame member implanted in a coronary sinus according to an aspectof the invention;

FIG. 4 d is a perspective view of yet another exemplary embodiment of acurved frame member for implantation in a coronary sinus according to anoptional aspect of the invention;

FIG. 4 e is a perspective view of yet another exemplary embodiment of acurved frame member for implantation in a coronary sinus according to anaspect of the invention;

FIG. 4 f is a perspective view of yet another embodiment of a curvedframe member for implantation in a coronary sinus according to an aspectof the invention;

FIG. 4 g is a perspective view of the curved frame member of FIG. 4 f ina curved configuration;

FIG. 4 h is a perspective view of yet another exemplary embodiment of acurved frame member according to an aspect of the invention;

FIG. 4 i is a perspective view of the curved frame member of FIG. 4 h ina curved configuration;

FIG. 5 a is a long axis, partial, cross-sectional view of a heart with asnare device delivered to the mitral valve according to an exemplaryembodiment of the invention;

FIG. 5 b is a short axis, cross-sectional view of a heart with filamentsdelivered to the mitral valve and captured by the snare device of FIG. 5a according to an exemplary embodiment of the invention;

FIG. 5 c is a long axis, partial, cross-sectional view of a heart withthe filaments of FIG. 5 b drawn through the left atrium by the snaredevice according to an exemplary embodiment of the invention;

FIG. 5 d is a short axis, cross-sectional view of a heart showing anembodiment of a floating ring device implanted to treat the mitral valveaccording to an optional aspect of the invention;

FIG. 5 e is a perspective view of an exemplary embodiment of a floatingring device according to an aspect of the invention;

FIG. 6 a is a short axis cross-sectional view of a heart showing anexemplary embodiment of an annular noose implanted to treat the mitralvalve according to an aspect of the invention;

FIG. 6 b is a cross-sectional view of a mitral valve with anotherexemplary embodiment of an annular noose implanted to treat the mitralvalve according to an aspect of the invention;

FIG. 6 c is a cross-sectional view of a mitral valve with yet anotherexemplary embodiment of an annular noose implanted to treat the mitralvalve according to an aspect of the invention;

FIG. 6 d is a short axis cross-sectional view of a heart with anotherexemplary embodiment of an annular noose implanted to treat the mitralvalve according to an aspect of the invention;

FIG. 6 e is a short axis cross-sectional view of a heart with anotherexemplary embodiment of an annular noose according to an aspect of theinvention;

FIG. 7 a is a short axis, cross-sectional view of a heart showing anexemplary embodiment of an elongate bar and a snare device around theelongate bar implanted to treat the mitral valve according to an aspectof the invention;

FIG. 7 b is a short axis, cross-sectional view of a heart showing anembodiment of an internal strut device implanted to treat the mitralvalve according to an optional aspect of the present invention;

FIG. 8 is a short axis, cross-sectional view of a heart implanted withan exemplary embodiment of an intrawall splint according to an aspect ofthe invention;

FIG. 9 is a partial perspective view of a heart implanted with anexemplary embodiment of an external plication device according to anaspect of the invention;

FIG. 10 a is a schematic side view of an improperly functioning mitralvalve during systole;

FIG. 10 b is a schematic side view of the valve of FIG. 10 a with anexemplary embodiment of a plug device implanted in the valve orificeaccording to an aspect of the invention;

FIG. 11 a is an exemplary embodiment of a spherical plug deviceimplanted in the valve orifice between the valve leaflets according toan aspect of the invention;

FIG. 11 b is an exemplary embodiment of an ellipsoidal plug deviceimplanted in the valve orifice between the valve leaflets according toan aspect of the invention;

FIG. 11 c is an exemplary embodiment of a disk-shaped plug deviceimplanted in the valve orifice between the valve leaflets according toan aspect of the invention;

FIG. 11 d is an exemplary embodiment of a wing-shaped plug deviceimplanted in the valve orifice between the valve leaflets according toan aspect of the invention;

FIG. 11 e is an exemplary embodiment of a sheet-like plug deviceimplanted in the valve orifice between the valve leaflets according toan aspect of the invention;

FIG. 11 f is an exemplary embodiment of an inflatable sheet-like plugdevice configured to be implanted in the valve orifice between the valveleaflets according to an aspect of the invention;

FIG. 11 g(i) is a perspective view of an exemplary embodiment ofcollapsible tube plug device in its expanded configuration according toan aspect of the invention;

FIG. 11 g(ii) is a perspective view of the collapsible tube plug deviceof FIG. 11 g(i) in its collapsed configuration according to an aspect ofthe invention;

FIG. 11 h(i) is another exemplary embodiment of a collapsible plugdevice in its expanded configuration implanted in the valve according toan aspect of the invention;

FIG. 11 h(ii) shows the collapsible plug device of FIG. 11 h(i) in itscollapsed configuration implanted in the valve according to an aspect ofthe invention;

FIG. 11 i(i) is yet another exemplary embodiment of a collapsible plugdevice in its expanded configuration implanted in the valve according toan aspect of the invention;

FIG. 11 i(ii) shows the collapsible plug device of FIG. 11 i(i) in itscollapsed configuration implanted in the valve according to an aspect ofthe invention;

FIG. 11 j(i) is yet another exemplary embodiment of a collapsible plugdevice in its expanded configuration implanted in the valve according toan aspect of the invention;

FIG. 11 j(ii) shows the collapsible plug device of FIG. 11 j(i) in itscollapsed configuration implanted in the valve according to an aspect ofthe invention;

FIG. 11 k is an exemplary embodiment of a piston-like plug deviceimplanted in the valve according to an aspect of the invention;

FIG. 11 l(i) is another exemplary embodiment of a piston-like plugdevice shown in a collapsed configuration implanted in the valveaccording to an aspect of the invention;

FIG. 11 l(ii) shows the piston-like plug device of FIG. 11 l(i) shown inan expanded configuration implanted in the valve according to an aspectof the invention;

FIG. 11 m(i) is yet another exemplary embodiment of a plug device shownimplanted in the heart during systole according to an aspect of theinvention;

FIG. 11 m(ii) shows the plug device of FIG. 11 m(i) shown implanted inthe heart during diastole according to an aspect of the invention;

FIG. 12 is a partial perspective view of the heart showing a plug deviceimplanted in the heart according to an optional aspect of the invention;

FIG. 13 a is a long axis cross-sectional view of the left ventricle andleft atrium of a heart showing schematically various exemplary positionsfor a plug device according to an optional aspect of the invention;

FIG. 13 b is a long axis cross-sectional view of the left ventricle andleft atrium of a heart showing schematically various exemplary positionsfor a plug device according to an aspect of the invention;

FIG. 13 c is a basal cut away cross-sectional view of the heart showingschematically various exemplary positions for a plug device according toan aspect of the invention;

FIG. 13 d is a long axis cross-sectional view of the left ventricle andleft atrium of a heart showing schematically an exemplary position for aplug device according to an aspect of the invention;

FIG. 14 a is a partial perspective view of the left ventricle and leftatrium of a heart showing an exemplary embodiment of a needle and styletassembly for delivering a plug device according to an aspect of theinvention;

FIG. 14 b is a long axis cross-sectional view of the heart showing theplacement of the needle and stylet assembly of FIG. 14 a relative to themitral valve leaflets according to an aspect of the invention;

FIG. 14 c is a partial perspective view of the left ventricle and leftatrium with a leader assembly and sheath retaining a plug device beingadvanced through the needle of FIG. 14 a according to an aspect of theinvention;

FIG. 14 d is a partial perspective view of the left ventricle and leftatrium showing an exemplary embodiment of a sheath retaining a plugdevice being advanced through the heart according to an aspect of theinvention;

FIG. 14 e is a partial short axis cross-sectional view of the heartduring systole viewed from the top and showing an exemplary embodimentof a plug device implanted in the valve according to an aspect of theinvention;

FIG. 14 f is a partial short axis cross-sectional view of the heartduring diastole viewed from the top and showing an exemplary embodimentof a plug device implanted in the valve according to an aspect of theinvention;

FIG. 15 a is a perspective view of an exemplary embodiment of a trocarand needle assembly for delivery of a plug device according to an aspectof the invention;

FIG. 15 b is a perspective view of the trocar and needle assembly ofFIG. 15 a with an exemplary embodiment of a pusher assembly used toadvance an anchor of a plug device out of the trocar and needle assemblyaccording to an aspect of the invention;

FIG. 15 c is a perspective view of the trocar and needle assembly ofFIG. 15 a with an exemplary embodiment of plug member advanced out ofthe trocar and needle assembly according to an aspect of the invention;

FIG. 16 a is a perspective view of an exemplary embodiment of a plugdevice with a plug member in a folded configuration according to anaspect of the invention;

FIG. 16 b is a partial perspective view of a left ventricle and leftatrium with the plug device of FIG. 16 a delivered to the heart in afolded configuration according to an aspect of the invention;

FIG. 16 c is a partial perspective view of a left ventricle and leftatrium showing an exemplary embodiment for unfolding the plug member ofFIG. 16 a according to an aspect of the invention;

FIG. 16 d is a partial perspective view of a left ventricle and leftatrium showing the plug device of FIG. 16 a implanted in the heart in anunfolded configuration according to an aspect of the invention;

FIG. 17 a is a cross-sectional view of the heart showing an exemplaryembodiment of an endovascular delivery path for delivering a plug deviceaccording to an aspect of the invention;

FIG. 17 b is a cross-sectional view of the heart showing anotherexemplary embodiment of an endovascular delivery path for delivering aplug device according to an aspect of the invention;

FIG. 17 c is a cross-sectional view of the heart showing yet anotherexemplary embodiment of an endovascular delivery path for delivering aplug device according to an aspect of the invention;

FIG. 18 a is a perspective view of an exemplary embodiment of a plugdevice and anchoring frame according to an aspect of the invention;

FIG. 18 b is a long axis partial cross-sectional view of the heartshowing an exemplary embodiment of the implantation of the plug deviceand anchoring frame of FIG. 18 a according to an aspect of theinvention;

FIG. 19 is a long axis partial cross-sectional view of the heart showingan exemplary embodiment of an inflation device and a plug device havingan inflatable plug member and anchors according to an aspect of theinvention; and

FIG. 20 is a perspective view of an exemplary embodiment of aninflatable plug device according to an aspect of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Certain aspects of the invention that will be discussed herein generallypertain to devices and methods for treating valve insufficiency arisingfrom heart conditions, including, for example, ventricle dilatation,valve incompetencies, congenital defects, and other conditions. Thevarious devices to be described may operate passively in that, onceimplanted in the heart, they do not require an active stimulus, eithermechanical, electrical, or otherwise, to function. Implanting one ormore of the devices of the present invention may assist in closing avalve to prevent regurgitation by, for example, assisting in the propercoaptation of the heart valve leaflets, either against one another orindependently against another surface. Assisting this coaptation may beaccomplished by directly geometrically altering the shape of thedysfunctional mitral valve annulus, by repositioning one or both of thepapillary muscles to a more normal state, and/or by otherwisefacilitating annular contraction during systole. In addition, thesedevices may be placed in conjunction with other devices that, or maythemselves function to, alter the shape or geometry of one or more heartventricles, locally and/or globally, and thereby further increase theheart's efficiency. That is, the heart may experience an increasedpumping efficiency and concomitant reduction in stress on the heartwalls through an alteration in the shape or geometry of one or more ofthe ventricles and through an improvement in valve function.

The inventive devices and related methods may offer numerous advantagesover the existing treatments for various valve insufficiencies. Thedevices are relatively easy to manufacture and use, and the surgicaltechniques and tools for implanting the devices of the present inventiondo not require the invasive procedures of current surgical techniques.For instance, the surgical techniques do not require removing portionsof the heart tissue, nor do they necessarily require opening the heartchamber or stopping the heart during operation. All of the techniquesdescribed may be performed without placing the patient oncardiopulmonary bypass, which, as discussed above, is routinely requiredfor conventional procedures to repair and/or replace the mitral valve.Avoiding placing the patient on cardiopulmonary bypass may permit theinventive devices and related methods to be adjusted “real time” so asto optimize the performance of the valve. Furthermore, the inventivedevices and related methods may avoid the need to place the patient onlong-term anticoagulation, which currently is required for many currentvalve repair techniques. For these reasons, the surgical techniques forimplanting the devices of the present invention also are less risky tothe patient than other techniques. The less invasive nature of thesurgical techniques and tools of the present invention may also allowfor earlier intervention in patients with heart failure and/or valveincompetencies.

Although many of the methods and devices are discussed below inconnection with their use in the left ventricle and for the mitral valveof the heart, these methods and devices may be used in other chambersand for other valves of the heart for similar purposes. The leftventricle and the mitral valve have been selected for illustrativepurposes because a large number of the disorders that the presentinvention treats occur in connection with the mitral valve. Furthermore,as will be shown, certain devices disclosed herein for improving valvefunction can be used either as stand-alone devices (i.e., solely fortreatment of valve insufficiency) or in conjunction with other devicesfor changing the shape of a heart chamber or otherwise reducing heartwall stress.

Reference will now be made in detail to some optional embodiments of theinvention, examples of which are illustrated in the accompanyingdrawings. Wherever possible, the same reference numbers will be usedthroughout the drawings to refer to the same or like parts.

FIG. 1 a is a short-axis cross-sectional view of the heart illustratingthe mitral valve MV in relation to the other valves of the heart,namely, the aortic valve AO, the tricuspid valve TV, and the pulmonaryvalve PV. The mitral valve has two leaflets, an anterior leaflet A and aposterior leaflet P. The anterior leaflet A is adjacent the aorta, AO,and the posterior leaflet P is opposite the aorta AO. An annulus ANsurrounds the mitral valve leaflets. FIG. 1 b is a partial short-axiscross-sectional view showing the mitral valve MV in relation to thecoronary sinus CS. The coronary sinus CS wraps around a significantportion of the posterior aspect of the mitral valve annulus AN. Theostium OS of the coronary sinus CS drains into the right atrium RA.

In FIGS. 2 a and 2 b, a top view of a properly functioning mitral valveMV is shown. FIG. 2 a shows the valve MV in its open position duringdiastole in which the posterior leaflet P is separated from the anteriorleaflet A. Portions of the chordae C also can be seen in FIG. 2 a. FIG.2 b shows the properly functioning mitral valve MV in the closedposition during systole. In this figure, the anterior leaflet A and theposterior leaflet P contact one another along a line of coaptation toclose the mitral valve MV and prevent blood from flowing through thevalve MV from the left atrium to the left ventricle.

FIG. 2 c shows a top view of an improperly functioning mitral valve MVin the “closed” position (i.e., during systole). In FIG. 2 c, theanterior leaflet A and the posterior leaflet P do not properly co-aptwhen the valve MV is in the closed position. This may be caused by, forexample, a dilatation of the annulus AN caused by an enlargement of theleft ventricle, or other similar mechanisms discussed above. As shown inFIG. 2 c, this improper coaptation prevents the complete closure of theorifice O between the valve leaflets, thereby permitting blood to leakthrough the valve from the left ventricle to the left atrium duringsystole. In other words, although the mitral valve is in a contractedstate, it is not actually closed so as to prevent blood flowtherethrough since the leaflets are prevented from completely comingtogether.

FIG. 3 a shows a side view of a properly functioning mitral valve in theclosed position with the valve leaflets L properly coapted so as toprevent blood flow through the valve. FIG. 3 b shows a side view of animproperly functioning mitral valve in which the valve leaflets L arenot properly coapted due to, for example, dislocation of the papillarymuscles PM. Such dislocation of the papillary muscles also may be causedby enlargement of the left ventricle, for example. The arrows in FIG. 3a show the movement of the papillary muscles PM down and to the rightresulting from such ventricle dilatation.

Such dysfunctioning valves, as shown in FIGS. 2 c and 3 b, may cause areduction in forward stroke volume from the left ventricle. Also, ablood flow reversal into the pulmonary veins may occur. Mitral valveregurgitation may also arise from a combination of valve annulusdilation and papillary muscle dislocation.

It should be noted that dilatation of the left ventricle represents anexample of a condition that can lead to improper valve function. Otherconditions, discussed above, also may cause such valve dysfunction, andthe devices and techniques discussed herein can be used to treat valveinsufficiencies caused by these conditions.

Exemplary embodiments of a device for treating the mitral valve via achange in shape of the valve annulus, which may include a reduction inthe effective circumference of the valve annulus, are shown in FIGS. 4a-4 i. The devices of FIGS. 4 a-4 i may be implanted on a beating heart,without the need for cardiopulmonary bypass. The devices of FIGS. 4 a-4i comprise curved frame members configured to be inserted into thecoronary sinus to effect a shape change of the posterior aspect of themitral valve annulus. In certain embodiments, as will be discussed, theframe members include mechanisms that allow for creating a focused shapechange at selected locations along a portion of the mitral valve annulusadjacent the frame members. That is, the frame members may allow fordiffering shape change effects along the length of the frame member. Theability to selectively alter the shape in one region of the annulusdifferently than another region may be particularly advantageous whentreating patients whose mitral valve insufficiency has arisen from localmyocardial ischemia or infarction, since such patients may experiencerelatively localized geometrical alterations of the mitral valveannulus, as opposed to an overall radial increase of the annulus.

As shown in FIG. 4 a, a curved frame member 110 a is configured to bedelivered endovascularly to and implanted in the coronary sinus CS. Theorigin of the coronary sinus CS is located in the wall of the rightatrium (not shown), and may be accessed by, for example, catheterizationof the femoral, jugular, or subclavian veins, so as to endovascularlyimplant the frame member 110 a. Alternatively, the frame member 110 acould be implanted via a surgical approach. In any case, the framemember 110 a may be positioned in the coronary sinus CS proximate theposterior aspect of the mitral valve annulus, as shown in FIG. 4 a. Inthis position, the frame 110 a may be used to alter the shape of theposterior aspect of the valve annulus, creating a configuration thateffectively reduces the annular circumference and/or creates a greaterdegree of coaptation between the anterior and posterior leaflets A, P.Alternatively, the frame member 110 a may be used to stabilize the shapeof the posterior aspect of the valve annulus, thereby substantiallypreventing continued dilation or deformation of the valve annulus.

The frame member 110 a may be made of a substantially rigid materialsuch that the frame member 110 a can be bent or otherwise formed intothe desired shape and placed within the coronary sinus CS, causing theannulus of the mitral valve MV, or portions thereof, to change shape.The frame member 110 a may engage within the coronary sinus CS via afriction fit to maintain its position within the coronary sinus CS. Afurther alternative is to fabricate the frame member 110 a of a shapememory material, such as nickel-titanium alloy, for example. In thismanner, the frame member 110 a may be chilled prior to implantation suchthat it has some flexibility. This may permit the frame member 110 a tobe introduced into the coronary sinus CS in a relatively atraumaticmanner. Once in place, the blood may warm the frame member 110 a,causing a shape change to a preformed initial shape. This shape changeof the frame member 110 a may in turn alter the shape of the coronarysinus CS and thus the valve annulus.

As shown in FIG. 4 b, one or both ends of the frame member 110 a mayexit the coronary sinus CS and anchor assemblies 105 may be provided onthe ends of the frame member 110 a. This may allow the frame member 110a to impart a shape change to the valve annulus beyond the somewhatlimited extent of the coronary sinus CS around the posterior aspect ofthe valve. The frame member 110 a may be anchored to an exterior surfaceof the heart wall via the anchor assemblies 105. The ends of the framemember 110 a may puncture through the coronary sinus CS to passexternally and allow connection of the anchor assemblies 105 to theexterior surface of the heart. The anchor assemblies 105 may be in theform of anchor pads. Some examples of such anchor pads are described inU.S. application Ser. No. 09/680,435, incorporated above. The anchorassemblies 105 may be sutured, or secured by other similar attachmentmechanisms, such as by providing a surface of the anchor assemblies 105with a tissue ingrowth promoting material, to an exterior surface of theheart wall to hold the frame 110 a in place with respect thereto. Tofurther facilitate obtaining the desired shape change of the mitralvalve annulus, the anchor assemblies 105 may be positionable along thelength of the frame member 110 prior to fixation of the frame member 110with respect to the heart or the frame member 110 may have a variablelength. For example, the frame member 110 a may be provided with atelescoping mechanism or the like.

In yet another exemplary embodiment, as shown in FIG. 4 c, the framemember 110 c may be configured to anchor itself into the vessel wall inorder to maintain its position. For example, in the optionalconfiguration shown in FIG. 4 c, the frame member 10 c is provided withbarbs 111 along its length. The frame member 110 c may be deliveredendovascularly such that the barbs 111 do not engage the wall of thecoronary sinus CS. Once the frame member 110 c is placed within thecoronary sinus CS in the desired position, it may be manipulated, forexample, by rotation or by moving the frame member 110 c in a directionopposite to the direction of advancement through the coronary sinus CS,so as to engage the barbs 111 with the coronary sinus wall. Thisengagement helps to maintain the position of the frame member 110 c.

FIG. 4 d shows another embodiment of a curved frame member 110 dconfigured to be implanted in the coronary sinus CS for treating themitral valve. In this embodiment, the frame member 110 d may support ashape change element 106 configured to move along a length of the framemember 110 d. The shape change element 106 may be configured to protruderadially with respect to the frame 110 d, thereby providing a morelocalized shape change in an area along the posterior aspect of themitral valve. A desired location for the shape change may be determinedby moving the shape change element 106 along the length of the framemember 110 d to a particular position and viewing the effects on mitralvalve function through real-time imaging techniques. The shape changeelement 106 also may be detachable from the frame member 110 d for easyremoval from the frame member 110 d if the localized shape change is nolonger desired. The shape change element 101 may be mechanicallydetachable or it may be detached electrolytically in a manner similar tothe detachment mechanism of the Guglielmi detachable coil. A deliverytool, which may be in the form of a delivery wire 106′, may be used todeliver the shape change element 101 over the frame member 11 d.

FIG. 4 e shows another exemplary embodiment of a curved frame forinsertion into the coronary sinus proximate the posterior aspect of themitral valve. In this embodiment, the frame member 110 e serves as asupport for an adjustable shape change member 107. As an example, thecurved frame 110 e may define at least one slot 108 extending along atleast part of the length of the frame 110 e. A moveable pin 109 mayengage with the slot 108 so as to slide along the length of the slot108. A wire 112 may extend along the portion of the curved frame 110 ethat lies adjacent the posterior aspect of the mitral valve annulus. Thewire 112 may have one end attached to the pin 109 and an opposite endattached at an end of the frame 110 e substantially opposite to themoveable pin 109. For example, as shown in FIG. 4 e, the wire 112 may beattached to a fixed pin 109′. Alternatively, the wire may attachdirectly to the frame member 110 e. Upon movement of the pin 109 towarda center of the frame member 110 e, the wire 112 curves, forming a bulgethat causes the mitral valve annulus to change shape.

The frame member 110 e optionally may have two pins disposed at oppositeends of the frame in either a single slot running substantially theentire length of the frame 110 e or two different slots disposed atsubstantially opposite ends of the frame 110 e. In an exemplaryembodiment, both of the pins 109, 109′ shown in FIG. 4 e, may bemoveable. In either case, the movement of one pin or both pins may causethe wire 112 to bulge outward, thereby imparting a variable degree ofshape change to the mitral valve annulus. Preferably, the wire 112 issufficiently flexible so as to permit bending of the wire due to themovement of the pin 109 within the slot 108. However, the wire 112 alsoshould be sufficiently rigid so as to maintain its bulged configurationand cause the desired shape change and/or repositioning of the valveannulus and/or papillary muscles.

FIGS. 4 f and 4 g illustrate yet another exemplary embodiment of acurved frame member 110 f for implanting in the coronary sinus to alterthe shape of the mitral valve annulus. FIG. 4 f is a perspective view ofthe frame member 110 f, which is formed from segments 113 configured torotate relative to each other. Rotating the segments 113 about theirrespective longitudinal axes and relative to each other may alter thecurvature of the frame 110 f along its length so as to produce variousdegrees of curvature in particular locations as desired. Such curvatureof the frame member 110 f is illustrated in FIG. 4 g. As a directsurgical implant, the curved frame member 110 f can have its segments113 individually manipulated via direct rotation to achieve a desiredfinal shape prior to insertion into the coronary sinus CS. A wire (notshown) extending down the center of the segments 113 may hold thesegments 113 in their final desired configuration, for example, due tofrictional engagement.

In another contemplated embodiment, shown in FIGS. 4 h and 4 i, a curvedframe member 110 h may comprise an actuation mechanism 90 attached to aportion of the frame member 110 h. For example, the actuation mechanism90 may be attached to a distal end of the frame member 110 h. The framemember 110 h may be formed of a plurality of substantially wedge-shapedsegments 95. Actuating the actuation mechanism 90, by, for example,pulling mechanism 90 proximally, causes the distal end to retract so asto change the shape of the frame member 110 h, as shown in FIG. 4 i.This in turn may alter the shape of the mitral valve annulus when theframe member 110 h is implanted in the coronary sinus CS. The actuationmechanism 90 may comprise a pull-actuated wire attached to a distal endof the frame member, as shown in FIGS. 4 h and 4 i, or alternatively toan anchor assembly provided on the distal end of the frame member. Thedesired final shape of the frame member 110 h may reduce or enlarge aradius of curvature of the valve annulus, or a combination of both,i.e., increasing the curvature in some regions and decreasing thecurvature in other regions.

The various curved frame devices of FIGS. 4 a-4 i may be configured tobe implanted on a beating heart. Optionally, the frame devices may beimplanted during an open chest or minimally invasive thoracic surgicalprocedure. For example, the frame member may be directly inserted intothe coronary sinus through an incision in either the right atrium or thecoronary sinus. In an alternative exemplary embodiment, the framedevices could be implanted endovascularly into the coronary sinus usingcatheter-based delivery techniques. For example, a catheter may beinserted into either the jugular vein or the vena cava and into theright atrium and then the coronary sinus.

FIGS. 5 a-5 e show an exemplary embodiment of a floating ring device fortreating mitral valve dysfunction by altering the shape of the mitralvalve annulus. The floating ring device according to the invention maybe implanted into the region of the mitral valve annulus itself (eitherabove, at, or below the annulus) in order to effect the desired shapechange of the mitral valve annulus.

A short axis cross-sectional view of the heart implanted with anexemplary embodiment of a floating ring device 115 is shown in FIG. 5 d.The device comprises a semi-flexible ring 116 configured to be placed inthe left atrium proximate the mitral valve annulus. A plurality oftightening members 117, may have the form of tension members, aresecured to the ring 116. An anchor mechanism, for example in the form ofa pad 118, attaches to the free end of each tightening member 117opposite to the ring 116. The anchor pads 118 are adapted to be securedto the tightening members 117 and placed externally of the heart wall,for example on the posterior wall of the left atrium LA, to secure thefloating ring device 115 in place with respect to the heart. Prior tosecuring the anchor pads 118 to the tightening members 117, thetightening members 117 may be tightened (i.e., their lengths between thevalve annulus and heart wall altered) until the desired annular shape ofthe mitral valve is obtained. The tightening members 117 may beindividually tightened to produce differing effects on the shape of themitral valve annulus depending on the position around the annulus. Theflexibility of the ring 116 also may assist in producing a varyingeffect on the mitral valve annulus geometry. It is contemplated thatsutures or other attachment mechanisms may be employed instead of theanchor pads 118 to secure the tightening members 117 to the heart wallonce the desired tensioning of the tightening members 117 has beenachieved.

Referring to FIGS. 5 a-5 d, an exemplary delivery technique forimplanting a floating ring device will be described. The techniquedescribed preferably is performed on a beating heart. As shown in FIG. 5a, a snare 119 is first delivered through a relatively small incision inthe wall of the appendage of the left atrium LA. As an example, theincision may be made at a location superior to the mitral valve MV. Atrocar (not shown) also may assist in the delivery of the snare 119through the incision. The snare 119 comprises a loop portion 119 a at adistal end of the device and a handling portion 119 b extending from theloop portion 119 a. The handling portion 119 b forms a proximal end ofthe snare 119. The handling portion 119 b may extend out of the leftatrium upon deployment of the snare 119 within the heart. According toan alternative aspect, the snare 119 may be delivered through the venoussystem to the right atrium (not shown) and then into the left atrium LAvia the atrial septum. In either case, once the snare 119 is deliveredinto the left atrium LA, the loop portion 119 a may be positioned withits perimeter resting on substantially the outermost edges of the mitralvalve annulus AN.

After appropriately positioning the snare 119 with respect to the mitralvalve annulus AN, a plurality of tightening members 117, which may havea substantially filament-like structure, may be inserted from externalthe heart, through the wall of the left atrium LA, and into the leftatrial chamber. For example, as shown in FIG. 5 b, a hollow, needle-likedelivery tool 300 may be used to insert the tightening members 117through the heart wall by inserting the delivery tool 300 carrying thetightening members 117 through the heart wall and ejecting the members117 out of the delivery tool 300.

As shown in FIG. 5 b, the tightening members 117 may be positioned alongthe posterior aspect of the mitral valve MV approximately at the levelof the mitral valve annulus AN. As the tightening members 117 areinserted into the atrial chamber, they may be carried through the snareloop 119 a via the blood flowing from the left atrium LA through themitral valve MV and to the left ventricle LV. To facilitate delivery ofthe tightening members 117; especially with regard to their insertionthe heart wall, the tightening members 117 optionally may be attached toneedles which penetrate the heart wall first. In this case, thebloodflow would carry the needles with the tightening members 117attached from the left atrium LA and through the snare loop portion 119a.

Once the tightening members 117 have been drawn through the snare loopportion 119 a, the snare 119 may then be retracted and the tighteningmembers 117 captured within the loop portion 119 a. By pullingproximally on the handling member 119 b, the snare 119 with the capturedtightening members 117 may be retrieved from the left atrium LA. Asshown in FIG. 5 c, the free ends of the tightening members 117 may bepulled out of the left atrium appendage through the incision previouslymade to insert the snare device 119. The snare device 119 may be removedfrom the tightening members 117 once they are pulled out of the leftatrium LA.

The free ends of the tightening members 117 may then be secured to theflexible ring 116, for example, by tying the ends to the ring. Theflexible ring 116 may then be reinserted into the left atrium LA bypulling on the tightening members 117 at their respective insertionpoints in the left atrial wall. Thus, the flexible ring 116 may beinserted through the same delivery path that was used to insert thesnare 119.

The flexible ring 116 preferably has enough flexibility so as to permitinsertion of the ring 116 into a trocar and/or an incision made in theleft atrial appendage and through the left atrium LA. Furthermore, thering 116 and the tightening members 117 preferably are covered with ahemocompatible material, such as expanded PTFE, for example. Thiscovering may facilitate the endothelialization of any portion of thering 116 and tightening members 117 residing in the blood flow path nearthe mitral valve.

After tightening each tightening member 117 to a desired amount, asecuring mechanism, such as the anchor pads 118 shown in FIG. 5 d, maysecure the tightening members 117 externally to the heart wall.Depending on the position and number of tightening members 117, and therelative degree of tightening of each, various annular geometries of themitral valve may be obtained. Echocardiographic visualization may beemployed to assist in adjusting the floating ring device. For example,the device can be selectively tightened in various locations and/or tovarious degrees until minimal or no mitral valve regurgitation isobserved using the echocardiographic visualization.

A further exemplary embodiment of a floating ring device is illustratedin FIG. 5 e. In this embodiment, the anterior-most pairs of tighteningmembers 117 e are relatively rigid. A single elongate anchor pad 118 econnects to the ends of each of the pairs of tightening members 117 e.In this manner, the position of the ring 116 over the central portion ofthe mitral valve may be maintained, even as the posterior-orientedtightening members 117 e are tightened.

Yet another optional embodiment of a device for treating the mitralvalve is illustrated in FIGS. 6 a-6 d. The device shown in these figuresis referred to herein as an “annular noose,” so-named due to itsnoose-like configuration. The annular noose 120 is formed from aflexible rope-like member 121. The member 121 may be made of a braidedpolyester, or other similar material, that allows the member 121 to flexwithout forming kinks and/or permanent bends. The rope-like member 121is shaped into a loop portion 122 that is placed around the exterior ofthe left atrium (not shown), as close as possible to theatrioventricular groove (not shown), and in substantially the same planeas the mitral valve annulus AN. It may be necessary for the portionbetween the anterior leaflet and the aorta to be passed through thetissue of the left atrium. An adjusting mechanism manipulable fromexternal the heart, such as a cinch ring 125, for example, may be usedto adjust the size of the loop portion 122 and secure the free ends 123a, 123 b of the member 121 that extend from the loop portion 122. Afterthe loop portion 122 has been properly positioned with respect to themitral valve annulus AN, the cinch ring 125 may be tightened, therebypermitting a reduction in the circumference of the mitral valve annulusAN.

FIGS. 6 b and 6 c show various elements that may be used in conjunctionwith the annular noose 120 of FIG. 6 a so as to provide a more focusedgeometrical shape change in selected regions of the mitral valve. Forexample, as shown in both FIGS. 6 b and 6 c, a relatively rigid member126 may be placed over the flexible member 121. In the optionalembodiment shown in FIGS. 6 b and 6 c, the relatively rigid member 126has a tubular configuration that may be advanced over either of the freeends of the flexible member 121 and positioned as desired along the loopportion 122. Alternatively, the relatively rigid member 126 may bepermanently secured to the loop portion 122 of the flexible member 121.In the embodiment of FIGS. 6 b, the annular noose 120, with therelatively rigid member 126 disposed thereon, is positioned with respectto the mitral valve MV such that the relatively rigid member 126 restsby the anterior leaflet side of the mitral valve MV. This placement maypermit a more focused circumferential reduction to take place at alocation proximate the posterior leaflet, since this portion is moreflexible and will tend to draw the noose down as it is tightened.

FIG. 6 c shows another embodiment of an element for use in conjunctionwith the annular noose 120. A shape change securing pad 127 may be usedfor adjusting the size of the loop portion 122 and for securing the freeends 123 a, 123 b. As shown in FIG. 6 c, the shape change pad 127 mayhave a substantially disk-like configuration with a central,substantially longitudinal passage through which the ends 123 a, 123 bof the flexible member 121 extend. A securing pin 128 may operate tomove toward and away from the center of the pad to pass through theflexible members ends 123 a, 123 b and secure the annular noose 120 intoposition. A surface 129 of the pad 127 that faces the mitral valveannulus may have a substantially non-concave profile, for example thesurface 129 may be either convex or flat. When the pad 127 is moved soas to tighten the annular noose 120, the pad 127 may press against themitral valve annulus and thereby cause a relatively focused shape changein the region of the pad 127.

As shown in FIG. 6 d, a plurality of pads 127 may be used to change theshape of the mitral valve in the regions of the mitral valve proximatethe pads. Such a focused change may permit increased co-aptation of thevalve leaflets in the various regions of the focused shape change. Theshape change pad 127 and the relatively rigid member 126 may be usedeither in combination, as shown in FIG. 6 c, or individually to create afocused shape change of the mitral valve. Such a focused shape change isin addition to the overall circumferential reduction achieved by theannular noose 120 alone.

FIG. 6 e illustrates an alternative exemplary embodiment of a noosedevice. The noose device in FIG. 6 e comprises a relatively rigid member126 e, similar to the relatively rigid member 126 of FIG. 6 b. Themember 126 e is positioned on the posterior side of the mitral valve MV.Preferably, the rigid member 126 e, which is placed on the loop portion122, may be formed by bending or the like to a desired shape so as toimpart a desired shape change to the posterior annulus. The rigid member126 e can be of any desired shape, and may include one or more localregions of indentations.

Another aspect of the present invention includes an internal strutdevice that operates to treat mitral valve dysfunction by causing ashape change to the mitral valve annulus while maintaining or restoringthe normal distance between the trigones of the valve. The device alsomay move the posterior leaflet face closer to the anterior leaflet face.Combined, these movements tend to increase the coaptation area of themitral valve leaflets and improve mitral valve function. An exemplaryembodiment of an internal strut device is shown in FIGS. 7 a and 7 b.

The embodiment of the internal strut device shown in FIGS. 7 a and 7 bgenerally comprises a relatively rigid elongate member 130 positioned soas to extend substantially along the line of leaflet coaptation of themitral valve. The relatively rigid elongate member 130 may be positionedin close proximity to the valve annulus AN, either slightly above orslightly below the annulus AN, so as to appropriately affect the valveleaflets and move them into a desired position. A second elongate member136 may be provided so as to extend substantially perpendicular to therelatively rigid elongate member 130 and to the line of leafletcoaptation. The relatively rigid elongate member 130 may be fixed to theouter walls of the left atrium or the left ventricle, depending on thepositioning of the member 130 with respect to the mitral valve MV.Sutures, anchor pads, or other similar mechanisms may secure the member130 with respect to the leaf. FIGS. 7 a and 7 b illustrate the use ofanchor pads 132 for securing the relatively rigid, elongate member 130.

Providing a relatively rigid elongate member 130 may substantiallyprevent the member from bending or buckling, which may in turn help tomaintain the desired trigonal distance. The member 130 may be a rigidbar made from biocompatible metals, such as nitinol, titanium,chrome-alloys, MP-35N, and other similar metals, or from biocompatiblepolymers, such as PEEK, acetyl, or other similar materials. Optionally,the bar may be an extendable, telescoping bar (not shown). This maypermit the length of the bar to be adjusted as necessary to optimize thetrigonal distance.

The second elongate member 136 may optionally be in the form of a snarehaving a loop portion 136 a that is secured around the relatively rigidmember 130. The snare may be tightened as desired and the free end 136 bmay be secured via an anchor pad 134 placed adjacent an exterior surfaceof the heart wall. Once secured, the snare essentially forms a tensionmember anchored at one end to the relatively rigid member 130 and at theopposite end to the heart wall. Together, the relatively rigid member130 and the second elongate member 136 impart a shape change to themitral valve annulus, while maintaining the distance between the valvetrigones T. Alternatively, the distance between the valve trigones alsomay be altered to achieve a more normal distance between them ifnecessary.

An exemplary embodiment for the delivery and implantation of theinternal strut device of FIGS. 7 a and 7 b will now be explained. Anintroducer 138, such as a trocar or other suitable introducer mechanism,may be inserted through the heart wall proximate the level of the mitralvalve annulus AN. As shown in FIG. 7 a, the introducer 138 may beinserted in a substantially perpendicular direction relative to the lineof coaptation of the mitral valve leaflets. Once the introducer isinserted, the second elongate member 136, in the form of a snare inFIGS. 7 a and 7 b, may be inserted through the introducer 138 andpositioned with the loop portion 136 a substantially in the middle ofthe mitral valve annulus AN. The relatively rigid elongate member 130may then be inserted through the left atrial wall (not shown) atapproximately the same annular level as the snare 136. However, themember 130 is advanced in a direction along the line of coaptation ofthe mitral valve leaflets and substantially perpendicular to the snare136. The member 130 may be passed through the loop portion 136 a of thesnare 136 and through the wall surrounding the left atrium locatedsubstantially opposite to the wall through which the member 130 wasinserted. Once extended transverse the left atrium LA, securingmechanisms, such as anchor pads 132, for example, may fix the member 130with respect to the heart. Prior to securing the member 130, its lengthbetween the chamber walls may be adjusted, as described above, in orderto alter the distance between the valve trigones as desired.

Once the relatively rigid elongate member 130 is secured into position,the snare loop portion 136 a may be tightened around it and the snare136 secured on the external surface of the atrial wall by a securingmechanism, such as anchor pad 134 as shown in FIG. 7 b. Thus, the snare136 also may induce a shape change to the mitral valve annulus AN, asshown by the indented region of the mitral valve annulus in FIG. 7 b.Both the relatively rigid elongate member 130 and the snare 136 may havetheir lengths adjusted as necessary to provide the overall desired shapechange of the mitral valve annulus. The snare 136 may optionally besecured using a securing mechanism that extends from the annular levelof the left atrium LA down the epicardial surface to a region proximatethe left ventricle LV. This would allow the strut device to change theshape of the mitral valve both at a level of the valve annulus and at asubvalvular level.

In an alternate embodiment (not shown), the relatively rigid bar may bereplaced by a splint assembly similar to the splint assemblies disclosedin U.S. application Ser. No. 09/680,435, incorporated by referenceherein. Such a splint assembly would be relatively flexible and capableof adjusting in length by adjusting the position of the anchor memberswith respect to the tension member of the splint assembly. The splintassembly may extend along the line of coaptation of the valve leaflets.In this case, the length of the tension member between the heart wallsmay be adjusted in order to maintain or achieve a more desirabletrigonal distance.

Yet another exemplary embodiment for treating a heart valve includes anintrawall splint comprising an elongate member configured to beimplanted within the heart wall so as to extend around a portion of thechamber. The elongate member may optionally be either wire-like, similarto the braided tension members used with the splint assemblies of U.S.application Ser. No. 09/680,435, incorporated by reference herein, ortubular. Because the device of this optional embodiment is implantedwithin and exterior to the heart wall, there is substantially no bloodcontact with the device, reducing the risk of thrombus formation.

An example of an intrawall splint 140 according to an exemplaryembodiment of the invention is shown in FIG. 8. The intrawall splint 140comprises an elongate member 141 that may be implanted within thelateral myocardial wall of the heart, optionally near theatrio-ventricular groove, in an area substantially coinciding with orslightly offset from the annular edge of the posterior leaflet. In theembodiment shown in FIG. 8, the elongate member 141 is secured to theheart using anchor assemblies 148, which may have configurations similarto those discussed with reference to FIGS. 4 b, 5 d, 7 a, and 7 b, forexample. The anchor assemblies 148 attach to the end portions of theelongate member 141 at an exterior surface of the heart wall. The anchorassemblies 148 may move along the length of the elongate member 141 toadjust the degree of compression on the heart wall. By appropriatelypositioning the anchor assemblies 148 on the elongate member 141, thearc length of the mitral valve annulus along the posterior side of thevalve may be reduced. This may increase the coaptation area between thevalve leaflets and decrease the annular cross-section. Once a suitabledegree of shape change of the valve annulus occurs, which may bedetermined by observing the mitral valve regurgitation through the useof echocardiagraphic or other similar visualization techniques, theanchor assemblies 148 may be fixed to the elongate member 141 to holdthe elongate member 141 in place with respect to the heart. The elongatemember 141 and the anchor assemblies 148 shown in FIG. 8 may beimplanted in a manner similar to the implantation techniques for thesplint assemblies of U.S. application Ser. No. 09/680,435, incorporatedby reference herein.

The elongate member 141 may be made of bio-inert, bio-stable, and/orbio-resorbable materials. In each of these cases, the implantation ofthe elongate member 141 within the heart wall may provoke a healingresponse by the heart wall. This healing response may elicit a chronicprocess that results in the shrinkage of the tissue in a direction alongthe axis of the elongate member. In another exemplary configuration, theelongate member 141 may be configured so as to deliver heat to the heartwall during delivery. Such heat also may initiate a healing response inthe heart wall tissue, resulting in tissue shrinkage along the elongatemember. For example, the member 141 may be made of a conductive metaland be heated, such as by temporarily exposing it to an electricalcurrent, preferably in the RF range. In an exemplary embodiment, the RFrange will be chosen so as to minimize electrical interference with theheart's conduction system.

Another exemplary embodiment of the invention includes an externalpliacation device that may be positioned on an exterior surface of theheart wall near the posterior mitral valve annulus in substantially thesame plane as the annulus. As with other devices discussed herein, suchan external plication device may be placed so as to reduce the valveannulus cross-section and increase the valve leaflet coaptation area.FIG. 9 shows an example of an external plication device 150 according toan aspect of the invention. The external plication device 150 comprisesa curved rod 151 anchored on an exterior surface of the heart wall by aseries of sutures 152. A series of tissue anchors may be used instead ofsutures. The rod 151 may be shortened, for example, by telescoping, to afixed length to provide a reduction of the lateral heart wall and/orposterior annular space. Alternatively, the external plication devicemay be implanted so as to reposition the papillary muscles, such as byreducing the intrapapillary distance, for example.

The rod 151 may be either relatively rigid or relatively flexible. Arelatively flexible rod 151 may take the form of a tension member, suchas the tension members used with the splint assemblies of U.S.application Ser. No. 09/680,435, incorporated by reference herein. Arelatively rigid rod may be preferable to provide a local shape change,while a relatively flexible rod may be preferable for changing the arclength of at least a portion of the valve annulus. The externalplication device may be made of biocompatible materials. Alternatively,the external plication device may be made of bioresorbable materialsthat provoke a chronic healing response of the heart wall tissue. Thishealing response may result in a scarring, causing the tissue to shrinkin a particular direction, thereby reducing the posterior annular arclength.

As with the intrawall splint device of FIG. 8, the external plicationdevice is implanted so as to substantially avoid blood contact withinthe heart chamber, which reduces the risk of thrombus formation.

The devices of FIGS. 8 and 9 are shown in position on the lateral wallof the heart proximate the posterior aspect of the mitral valve annulus.It is contemplated, however, that these devices may be implanted inother positions with respect to the heart while still helping to reducemitral valve regurgitation or to treat other heart valves altogether.

Yet another aspect of the invention includes the use of so-called “plug”devices, for treating incompetent heart valves. These plug devices areintended assist in closing the mitral valve to prevent regurgitation byincreasing the coaptation area of the mitral valve leaflets and/ordecreasing the coaptation depth of the mitral valve leaflets. Thisgenerally may be accomplished by placing a plug device in the “hole”between the valve leaflets (i.e., the valve orifice), thereby providinga surface against which the valve leaflets may abut (i.e, coapt), inorder to close the mitral valve during systole. The plug devicesdescribed herein assist in closing the mitral valve substantiallywithout altering the shape of the valve annulus and/or repositioning thepapillary muscles. To further understand how the plug devices accordingto optional aspects of the invention operate to improve mitral valvefunction, reference is made to the various optional embodiments of thedevice shown in FIGS. 10 b-11 m(ii).

FIG. 10 a illustrates a schematic side view of the leaflets L of adysfunctional mitral valve during systole. As seen in this figure, theleaflets L do not coapt so as to close the mitral valve orifice.Therefore, regurgitant flow will occur through the valve during systole.FIG. 10 b illustrates the valve of FIG. 10 a during systole with anexemplary embodiment of a plug member 160 of the present inventionimplanted in the valve leaflet coaptation space. As can be seen, thepresence of the plug member 160 will block the regurgitant flow throughthe valve during systole as the leaflets L abut against the outersurface of the plug member 160. In other words, the plug member 160“plugs” the valve orifice during systole to hinder or prevent blood fromleaking through the valve.

In the exemplary embodiments of FIGS. 11 a-11 f, a plug member issuspended in the coaptation space substantially in the area whereregurgitant blood flow occurs. The suspended plug member may have avariety of shapes depending on factors such as the mitral valvegeometry, the alignment of the valve leaflets, and the size and shape ofthe regurgitant opening during systole. For example, the suspended plugmember may have a spherical configuration (160 a in FIG. 11 a), anellipsoidal configuration (160 b in FIG. 11 b), a disk-shapedconfiguration (160 c in FIG. 11 c), a wing-like configuration (160 d inFIG. 11 d), or a sheet-like configuration (160 e in FIG. 11 e, 160 f inFIG. 11 f). FIGS. 11 a-11 e show schematically a partial cross-sectionalview of the mitral valve with the various plug members disposed betweenthe valve leaflets L and within the valve orifice.

In FIGS. 11 a-11 d, the valve is shown in an open position, with a spacebetween the valve leaflets L and the outer surface of the plug member160 a-160 d to allow blood flow therethrough. During closure of thevalve, the leaflets L abut against the outer surface of the plug member160 a-160 d, thereby preventing regurgitation through the valve orifice,which may otherwise occur if the leaflets are unable to properly coaptagainst one another. FIG. 11 e shows schematically a partialcross-sectional view of a mitral valve during systole with a plug member160 e disposed between the valve leaflets L. The presence of the plugmember 160 e permits the valve to close during systole as a result ofthe valve leaflets L coapting against the surface of the plug member 160e. This coaptation will substantially prevent regurgitant blood flowfrom occurring during systole.

A suspended member 160 d having a wing-like configuration, as shown inFIG. 11 d, may provide an advantageous surface for the valve leaflets Lto close against due to its tapered configuration. The taperedconfiguration substantially mutually corresponds to the profile of thevalve leaflets surfaces themselves. Such a tapered and mutuallycorresponding shape may help to reduce thrombus formation at theblood-surface contact points with the suspended member 160 d. Moreover,this shape may reduce insult to the valve leaflets L as they closeagainst the surface of the suspended member 160 d.

A suspended member 160 e having a substantially sheet-like configurationmay be particularly suitable for use as a plug device in patients havingmisaligned leaflets. In this case, as shown in FIG. 11 e, the ends ofthe valve leaflets L tend to reach the centerline of the valve as theycome together during systole. However, the leaflets L are arranged suchthat the ends of the leaflets L are in different transverse planes uponclosing of the valve, therefore hindering proper coaptation and valveclosure. The substantially planar plug member 160 e in FIG. 11 e may besuspended substantially along the centerline of the valve, providing themisaligned valve ends with a surface to abut against. Due to itssubstantially planar configuration, the plug member 160 e may minimizethe cross-sectional area of the blood flow path that is blocked by thedevice, while also providing the desired closure of the valve. In analternative embodiment, shown in FIG. 11 f, the sheet-like plug 160 fmay be constructed of two layers sealed along their perimeters. Thisembodiment therefore may form an inflatable structure. Such aninflatable plug member may permit the cross-section of the member to beselected and varied according to the size of the “hole” between theimproperly coapting valve leaflets.

As shown in the FIGS. 11 a-11 f, the plug members 160 operate to reducemitral valve regurgitation and improve valve function by providing asurface against which the mitral valve leaflets may coapt duringsystole, thereby closing the valve to blood flow therethrough. Thus,these plug members 160 may operate as plugs to close the hole otherwiseleft open due to the inability of the valve leaflets to properly coapt.Providing such a surface against which the mitral valve leaflets maycoapt may benefit both patients having valve leaflets with a reducedrange of motion, for example, due to chordal tethering, and/or patientshaving leaflets unable to coapt due to left ventricular dilatation. Theplug devices of FIGS. 11 a-11 f also may enhance coaptation in patientswhose leaflets are misaligned, since each leaflet may coapt with thesurface provided by the plug member independently of the other leaflet.

Materials suitable for construction of the various plug devicesdisclosed herein may be categorized generally into the following broadgroups: synthetic polymers, biological polymers, metals, ceramics, andengineered tissues. Suitable synthetic polymers may includeflouroethylenes, silicones, urethanes, poyamides, polyimides,polysulfone, poly-ether ketones, poly-methyl methacrylates, and othersimilar materials. Moreover, each of these compositions potentially maybe configured from a variety of molecular weights or physicalconformations.

Suitable metals may be composed from a variety of biocompatible elementsor alloys. Examples include titanium, Ti-6AL4V, stainless steel alloys,chromium alloys, and cobalt alloys. The stainless steel alloys mayinclude, for example, 304 and 316 stainless steel alloys. The cobaltalloys may include Elgiloy, MP35N, and Stellite, for example.

Suitable ceramic materials may be fashioned from pyrolytic carbon andother diamond-like materials, such as zirconium, for example. Thesematerials may be applied to a variety of core materials, such asgraphite, for example.

As for biological materials for manufacturing the devices, a variety offixed tissues may be useful in the fabrication process. Base materials,such as pericardium, facia mater, dura mater, and vascular tissues maybe fixed with a variety of chemical additives, such as aldehydes andepoxies, for example, so as to render them nonimmunogenic andbiologically stable.

Tissues also may be engineered to meet the intended purpose. Substratesmay be constructed from a variety of materials, such as resorbablepolymers (e.g., polylactic acid, polyglycolic acid, or collagen). Thesematerials may be coated with biologically active molecules to encouragecellular colonization. Additionally, these tissues may be constructed invitro, for example using the patient's own cells or using universal celllines. In this way, the tissue may maintain an ability to repair itselfor grow with the patient. This may be particularly advantageous in thecase of pediatric patients, for example.

Each of the previously mentioned materials also may be subjected tosurface modification techniques, for example, to make them selectivelybioreactive or nonreactive. Such modification may include physicalmodification, such as texturing; surface coatings, including hydrophilicpolymers and ceramics (e.g., pyrolytic carbon, zirconium nitrate, andaluminum oxide); electrical modification, such as ionic modification,for example; or coating or impregnation of biologically derivedcoatings, such as heparin, albumin, a variety of growth healingmodification factors, such as, for example, vascular endothelial growthfactors (VEGF), or other cytokines.

The tethers used to suspend the plug members, which will be described inmore detail shortly, may be constructed of either monofilament ormultifilament constructions, such as braids or cables, for example.Materials such as high strength polymers, including liquid crystalpolymers (Vectran) and ultra high molecular weight polyethylene fibers(Spectra) may be suitable to provide desirable mechanical and fatigueproperties. Suitable metals may include stainless steel, titaniumalloys, and cobalt-chrome alloys, for example.

The materials discussed above are exemplary and not intended to limitthe scope of the invention. Those skilled in the art would recognizethat a variety of other similar suitable materials may be used for theplug devices and suspension members disclosed herein.

The suspended plug members 160 a-160 f of FIGS. 11 a-11 f may beanchored to the heart walls using anchoring members such as, forexample, internal tissue anchors or anchor pads attached externally ofthe heart. An example of utilizing external anchor pads for suspendingthe plug members 160 within the valve orifice is illustrated in FIG. 12,which will be explained in more detail shortly.

Yet another exemplary embodiment of a plug device is illustrated inFIGS. 11 g(i), 11 g(ii). The device of FIGS. 11 g(i), 11 g(ii) comprisesa tubular member 167 that may be at least partially collapsible andflexible. The top portion of the tubular member 167 may include a ringstructure 168 that may be placed on the mitral valve annulus. Theremaining portions of the tubular member 167 may be placed through thevalve orifice between the valve leaflets such that the tubular member167 extends at least partially into the left ventricular chamber. Whenpressure in the left ventricle increases, such as during systole, forexample, the mitral valve leaflets may begin to close. As the leafletsbegin to close, the tubular member 167 collapses, as shown in FIG. 11g(ii), so as to close the tube 167 at its distal end. This closurecloses the blood flow path between the left atrium and the leftventricle. Once the pressure in the left atrium again becomes higherthan the pressure in the left ventricle, the tubular member 167 may opento allow bloodflow therethrough. The tubular plug member 167 itselftherefore provides a type of valving mechanism without the need toremove the natural valve or provide other mechanical valve devices.

Other embodiments of expandable/collapsible plug devices that operate toperform valving functions are shown in FIGS. 11 h-11 j. FIGS. 11 h(i),11 h(ii) illustrate a collapsible plug member 169 that has a hollow,tapered configuration. During diastole, as shown in FIG. 11 h(i), theplug member 169 has an expanded configuration so that blood can flowthrough the plug member 169 and also between the leaflets L and theouter surface of the plug member 169. The plug member 169 is configuredto collapse during systole, as shown in FIG. 11 h(ii), so that thebottom portion 169B of the plug facing the left ventricle is closed offto prevent blood flow through the plug 169. In the collapsedconfiguration, the member 169 maintains a relatively wide profile at atop portion 169T and tapers toward the bottom portion 169B where thesides of the plug member 169 come together to close the plug member 169to flow therethrough. The tapered sides also allow the valve leaflets toclose against the plug member 169 during systole. In this manner, bloodis substantially prevented from flowing through the mitral valve duringsystole.

FIGS. 11 i(i), 11 i(ii) show yet another exemplary embodiment of acollapsible and expandable plug member 170. The plug member 170 includestwo wing members 170 a, 17 b, and an articulation 171 connecting the twowing members 170 a, 170 b at their top ends. During systole, as shown inFIG. 11 i(i), the pressure in the left ventricle acts on the wingmembers 170 a, 170 b, causing them to pivot about the articulation 171in an outward direction (i.e., the wing members 170 a, 170 b pivot awayfrom each other). This pivoting outward of the wing members 170 a, 170 ballows the wing members 170 a, 170 b to abut with the valve leaflets L,thus closing the valve orifice to prevent bloodflow through the valve.

During diastole, as shown in FIG. 11 i(ii), pressure from the leftatrium causes the wing members 170 a, 170 b to pivot about thearticulation 171 in an inward direction (i.e., the wing members 170 a,170 b pivot toward each other). Thus, the wing members 170 a, 170 bseparate from the leaflets L, allowing blood to flow through the valvefrom the left atrium into the left ventricle.

Yet another exemplary embodiment of an expandable and collapsible plugdevice is shown in FIGS. 11 j(i), 11 j(ii). FIG. 11 j(i) shows acollapsible plug member 172 during systole and FIG. 11 j(ii) shows thecollapsible plug device 172 during diastole. During systole, the plugmember 172 essentially is in the form of a hollow cone with a base ofthe cone disposed proximate the free ends of the valve leaflets L. Thesides 172 a, 172 b of the cone take on a concave configuration duringsystole, as shown in FIG. 11 j(ii) so as to allow blood to flow betweenthe sides 172 a, 172 b and the valve leaflets L. During diastole, theblood flow through the valve will cause the plug member 172 to expand,thereby billowing the side walls 172 a, 172 b outwardly such that theyabut the valve leaflets L to restrict or prevent blood from flowingthrough the valve.

Another exemplary embodiment for a plug device may comprise a memberthat is suspended in place below the free edges of the valve leaflets ina plane substantially parallel to the valve annulus. Such a plug deviceis shown in FIG. 11 k. In this embodiment, a piston-like plug device 173having a disk member 174 suspended on the end of an elongate member 174′is movable along the longitudinal axis of the valve. The disk member174, which preferably has a circular or oval shape, is movable into andout of contact with the free ends of the valve leaflets L in accordancewith the bloodflow through the heart. In this manner, the piston-likeplug device 173 may operate similar to a one-way check valve, reducingregurgitation during systole by moving to seal the free ends of thevalve leaflets L with the disk-like member 174, as shown in FIG. 11 k,for example. During diastole, the piston-like plug device 173 may movein a direction toward the left ventricle such that the disk member 174moves out of contact with the free ends of the valve leaflets L. FIGS.11 l(i), 11 l(ii) show an alternative arrangement of the piston-likeplug device 173 of FIG. 11 k. In this embodiment, the disk member 174 lis made of a flexible or semi-flexible material. This material may allowthe disk member 174 l to obtain a reduced cross-sectional profile duringdiastole, as shown in FIG. 11 l(i), allowing for a relatively normalsize valve orifice blood flow area. During systole, the disk member 174l expands and inverts as pressure in the left ventricle increasescausing blood to flow toward the valve. The disk member 174 l envelopsthe ends of the valve leaflets L to substantially prevent regurgitantbloodflow through the valve, as shown in FIG. 11 f(ii).

Yet another alternative arrangement of a plug device is shown in FIGS.11 m(i), 11 m(ii). In this exemplary embodiment, the device 175 isimplanted such that a disk-like member 176 is situated substantiallyabove the level of the valve leaflets L proximate the valve annulus AN.As shown in the FIG. 11 m(i), the perimeter of the disk-like member 176contacts the upper portions of the valve leaflets L proximate the valveannulus AN as the pressure in the left ventricle increases duringsystole, moving the valve leaflets L toward one another. This contactfacilitates closure of the mitral valve orifice. On the other hand,during diastole, as shown in FIG. 11 m(ii), the leaflets L move awayfrom and out of contact with the disk-like member 176, allowing blood toflow between the disk-like member 176 and the valve leaflets L from theleft atrium LA in to the left ventricle LV.

The various devices shown in FIGS. 11 a-11 m(ii) can be delivered andimplanted in the heart using numerous approaches. FIG. 12 shows oneexample of an embodiment for implanting a plug device of the invention,indicated generally as 200, in the heart. In FIG. 12, the plug member201 is suspended from at least one elongate member 202. The elongatemember 202 optionally has a tether-like structure. Anchors 203 areprovided on the ends of the elongate member 202 to secure the device toexterior portions of the heart wall HW. The anchors 203 optionally maybe similar to the anchors discussed above with reference to FIGS. 4 band 5 d, for example. FIG. 12 shows an exemplary implantation position,namely a sub-annular position, for the plug device 200 with respect tothe heart.

Numerous other implantation positions for the plug devices, discussedabove with reference to FIGS. 11 a-11 m, are envisioned and areconsidered within the scope of the invention. Some examples of thesepositions are shown in FIGS. 13 a-13 d. The lines shown in these figuresrepresent the extension of the elongate member (or members) 202, fromwhich the plug member is suspended, between the anchors 203 secured tothe exterior portions of the heart wall HW. FIG. 13 a shows a long axiscross-sectional view (from the lateral side) of the left ventricle LVand left atrium LA. Each of the positions shown by lines A-D representsanterior-to-posterior positioning of a plug device. Line A represents asupra-annular, anterior-to-posterior position; line B represents asub-annular, anterior-to-posterior position; line C represents asupra-annular, anterior to sub-annular, posterior position, and line Drepresents a supra-annular, posterior to sub-annular, anterior position.FIG. 13 b shows various lateral-medial positions for a plug device. Thevarious positions are indicated by lines E-H in FIG. 13 b. Line Erepresents an intraventricular septum S to sub-annular, lateral wall LWposition; line F represents an intraventricular septum S tosupra-annular, lateral wall LW position; line G represents an atrialseptum AS to supra-annular, lateral wall LW position; and line Hrepresents an atrial septum AS to sub-annular, lateral wall LW position.FIG. 13 c shows a basal cut-away, cross-sectional view of the heart withthe various positions corresponding to lines A-H in FIGS. 13 a and 13 brepresented. FIG. 13 c also shows two additional optional positions,indicated by lines I and J, for the implantation of the plug devices.Line I represents an anterior-medial, supra-annular atrial wall AW tosupra-annular atrial wall AW position and line J represents ananterior-medial, supra-annular atrial wall AW to sub-annular atrial wallAW position. FIG. 13 d shows a long-axis cross-sectional view of theleft ventricle LV and left atrium LA with an apical wall APW to atrialwall AW position, indicated by line K.

The particular position selected to implant a plug device may depend ona variety of factors, such as the condition of the patient's heart,including the heart valves, the delivery technique utilized to implantthe device, the type of plug device utilized to treat the valve, andother similar factors. Each of the positions shown in FIGS. 13 a-13 d,however, permits proper positioning of the plug device to preventregurgitation and avoids damage to key coronary structure. Further,particular positions may be selected based on factors such as, forexample, the geometry, including size and shape, of the valve orifice.

The plug devices of FIGS. 11 a-11 m(ii) may be delivered to the heart inseveral ways, including ways that do not require placing the patient onbypass. Perhaps the most direct approach includes obtaining open chestaccess to the left ventricular and atrial walls. However, the devicesalso may be implanted using off-pump surgical techniques or endovasculartechniques.

An example of an approach for delivery of the plug device of FIG. 12 isillustrated in FIGS. 14 a-14 c. For exemplary purposes, the position ofthe plug device resulting from the delivery shown in FIGS. 14 a-14 ccorresponds to position B, as shown in FIGS. 13 a and 13 c. However,other positions for the plug device could be obtained using the deliveryapproach which will now be described. Moreover, plug devices other thanthat of FIG. 12 could be implanted via the delivery techniques to bedescribed.

In FIG. 14 a, a needle and stylet assembly 210 is passed through theleft ventricle LV between the mitral valve leaflets L. The stylet 211 isthen removed, as shown by the arrow in FIG. 14 a, leaving only thehollow needle 212 in place. The position of the needle 212 between theleaflets L is represented by the label X in FIG. 14 b. The plug devicemay then be delivered through the needle 212. Or, as shown in FIG. 14 c,a leader assembly 213 may be attached to the elongate member 1202 fromwhich the plug member 201 is suspended. The plug member 201 may have afolded configuration or may be a collapsible and expandable member. Asheath 214 may retain the plug member 201 during delivery across theheart chamber. An anchor pad 203 may be attached to the proximal end ofthe elongate member 202 during delivery. The anchor pad may optionallybe either fixed at a predetermined position on the elongate member 202or it may be movable with respect to the elongate member 202 so that itsposition is adjustable. The leader assembly 213 may be advanced throughthe heart wall at the side opposite to the side the needle 212 entered,and the needle 212 may then be removed from the heart. The leaderassembly 213 and the elongate member 202 may then be advanced furtheruntil the plug member 201 is extracted from the sheath 214. Thisextraction causes the plug member 201 to unfold. Once the plug member201 is fully extracted from the sheath 214 and appropriately positionedbetween the mitral valve leaflets, retaining sheath 214 may be removedfrom the heart and the leader assembly removed from the elongate member202. A second anchor pad 203 may be placed on the distal end of theelongate member 202 to hold the plug device in place, as shown in FIG.12.

An exemplary embodiment for delivering a plug device using a retainingsheath is illustrated in FIG. 14 d. Elongate member 202 may be connectedto a leader member (not shown), which may be in the form of a sharpenedneedle, or the like. The leader member is configured to pass through theheart wall and across the ventricle. As shown in FIG. 14 d, removal ofthe plug member 201 from the retaining sheath 214 may occur by advancingthe sheath 214 partially through the heart wall HW and pulling theelongate member 202 extending through the heart wall HW opposite to theretaining sheath 214. As the elongate member 202 is pulled, the plugmember 201 advances out of the distal end of the sheath 214. Once theplug member 201 advances entirely out of the distal end of the sheath214, it will have an unfolded or expanded configuration and may bepositioned as desired between the mitral valve leaflets L by pulling onthe elongate member (in the direction of the arrow shown in FIG. 14 d).

FIG. 14 e illustrates a top view of an implanted plug device, includingplug member 201, during systole, according to an exemplary embodiment ofthe invention. The plug member 201 is disposed between the valveleaflets L and occupies the position of the valve opening O throughwhich regurgitant flow would occur in the absence of valve treatment.FIG. 14 f shows a top view of the implanted plug device during diastole,when the valve leaflets A, P are opened. As shown, flow through thevalve O is permitted in the orifice space O between the leaflets A, Pand the plug member 201.

FIGS. 15 a-15 c illustrate another delivery tool that may be used inlieu of those discussed with reference to FIGS. 14 a-14 d. In thisembodiment, the elongate member 202, the folded plug member 201, and adeployable anchor member 218 may be retained in a trocar and needleassembly 216, as shown in FIG. 15 a. The assembly 216 may be insertedacross the heart such that it extends out of opposite heart walls andtransverse the mitral valve in any of the positions discussed withreference to FIGS. 13 a-13 d, or other suitable, desired positions. Apusher mechanism 217 may then be inserted through the proximal end ofthe trocar and needle assembly 216 to advance the plug device 200 fromthe distal end of the assembly 216. As shown in FIG. 15 b, an anchor 218attached to an elongate member 202 exits the assembly 216 first. Theanchor 218 is attached to the elongate member 202 so as to extendsubstantially perpendicularly to the elongate member 202. However, whenplaced in the assembly 216, the anchor 218 is turned with respect to theelongate member 202 such that it lies substantially parallel to theelongate member 202.

Once the anchor 218 has advanced out of the assembly 216, the pushermechanism may be removed and the assembly 216 and plug device 200 may beretracted back through the heart in a direction opposite to thedirection of advancement of the assembly 216 into the heart. As the plugdevice 200 is retracted with the assembly 216, the anchor 218 will catchon the external surface of the heart wall, preventing the plug device200 from being pulled back through the heart with the assembly 216. Theassembly 216 may continue to be retracted out of the heart and off ofthe plug device 200 until the plug member 201 eventually exits thedistal end of the assembly 216, as shown in FIG. 15 c. Upon exiting theassembly 216, the plug member 201 unfolds. The plug member 201 may thenbe positioned appropriately with respect to the mitral valve and, oncethe assembly 216 has been entirely removed from the plug device 200, ananchor (not shown) may be placed on the free end of the elongate memberopposite to the anchor 218 to secure the plug device 200 in position.

Yet another exemplary embodiment of a delivery technique for a foldedplug member is illustrated in FIGS. 16 a-16 d. In this embodiment, theplug member 201 may have a folded configuration and be attached to aplurality of elongate members 202 (e.g., tethers) for suspending theplug member 201 in the mitral valve orifice between the leaflets, asdescribed above. These elongate members 202 also assist in the unfoldingof the plug member 201. FIG. 16 a depicts the plug device 200 with theplug member 201 in a folded configuration and attached to four elongatemembers 202 a-202 d. The stylet and needle assembly, and the leaderassembly described above with reference to FIGS. 14 a-14 c may be usedto deliver the plug device 200 to the valve. In this manner, theelongate members 202 a and 202 d may be advanced together through theneedle assembly, for example, in a supra-annular position, as shown inFIG. 16 b. Once advanced, the elongate members 202 a and 202 d exit oneside of the left atrial wall and the elongate members 202 b and 202 cexit the left atrial wall at an opposite side. The plug member 201,still in a folded configuration, is suspended slightly above the annularlevel of the mitral valve MV adjacent the valve orifice.

To unfold the plug member 201, stylets 14 are attached to the free endsof the elongate members 202 c and 202 d. Using the needle stylets 14 toguide the free ends of the elongate members 202 c, 202 d, as shown inFIG. 16 c, each member 202 c, 202 d is advanced back through the heartto an opposite side and to a sub-annular position, thus exiting throughthe left ventricular wall on a side opposite to its original exitthrough the left atrial wall. This action causes the plug member 201 tounfold and extend between the valve leaflets. The elongate members 202a-202 d may then be secured with respect to the heart using externalanchors 203, as shown in FIG. 16 d. The plug device 200 in FIG. 16 dthus has a supra-annular, sub-annular position.

Other techniques for delivery and implantation of the plug devices ofthe invention are envisioned and are considered to be within the scopeof the invention. For example, the plug member and at least one of theanchor members may be inflatable so that during delivery the members canbe in a deflated configuration to facilitate passage through the heartwall or through a needle. As shown in FIG. 19, once the plug device 200(i.e., at least one anchor and the plug member 202) is placed in thedesired position relative to the mitral valve MV and heart wall HW, aninflator, which may optionally be in the form of a compressed air deviceor a needle 250 (as shown in FIG. 19) containing a fluid, such as PMMA(polymethylmethacrylate) P-HEMA (poly (2-hydroxyethyl methacrylate)),for example, may be connected to the elongate member and used to inflatethe plug member 201 and the at least one anchor member 203. The elongatemember in this case would be configured to allow passage of fluidtherethrough to the plug member and at least one anchor member.

FIG. 20 illustrates an additional exemplary embodiment of an inflatableplug device 350. The plug device comprises plug member 351 made of twosheets 351 a and 351 b attached to each other along the edges. The plugdevice 350 also comprises tethers 352, for example, four tethers 352attached to the plug member 351 proximate the corners of the sheets 351a, 351 b. At least one of the tethers 352 may define a lumen configuredfor fluid flow therethrough. The lumen may be in flow communication withthe plug member 351 so as to permit inflation of the plug member 351 viathe lumen. In this manner, the plug member 351 may be filled to thedesired shape and size as is needed to at least substantially preventregurgitation through the valve.

Endovascular delivery techniques, including, for example, catheter-baseddelivery techniques, also are envisioned as within the scope of theinvention. Such endovascular delivery techniques may be utilized incombination with the methods discussed with reference to FIGS. 14 a-19.For example, the plug devices may be delivered through a catheteradvanced through the lumen of the aorta AO and across the left atrialchamber LA, as shown in FIG. 17 a. Alternatively, as shown in FIG. 17 b,the delivery path may be through the lumen of the coronary sinus CS andthe coronary vein CV, and from the coronary vein CV across the leftatrial chamber LA. Yet another embodiment of an endovascular deliverypath is shown in FIG. 17 c. In this figure, the delivery path is throughthe lumen of the vena cava CV into the right atrial chamber RA andacross the left atrial chamber LA.

The techniques for implanting the plug devices discussed above includeextending elongate members, with the plug member suspended therefrom,substantially transversely from one wall of a heart chamber to anopposite wall of a heart chamber. In an alternative embodiment, shown inFIGS. 18 a and 18 b. The plug member may be suspended from an elongatemember that engages only on one side of the heart. Such a configurationmay alleviate the need to traverse the entire heart chamber, therebyminimizing risk of damaging internal cardiac structure.

FIG. 18 a shows an exemplary embodiment of a plug device 230 andanchoring frame 233 for engaging only one side of the heart to implantthe plug device 230. The plug member 201, shown as an ellipsoid plugmember in this figure, depends from a beam member 231 having ahorizontally extending portion 231 h and a shorter, vertically extendingportion 231 v. The plug member 201 is connected to the verticallyextending portion 231 v so that the plug member 201 is placed within thevalve orifice between the valve leaflets, as shown in FIG. 18 b.Optionally, a intramuscular ingrowth sleeve 232, made of a Dacronvelour, for example, may be placed around the horizontal portion 231 h.The function of this sleeve 232 will be explained with reference to thediscussion of the implantation of the device. The horizontal portion 231h connects to the anchoring frame 233 at an end opposite to the plugmember 201. The anchoring frame 233 has a substantially I-shapedconfiguration and the horizontal portion 231 h of the beam member 231connects to the vertical leg 233 v of the anchoring frame 233.

The horizontal legs 233 h of the anchoring frame are placed on theexternal surfaces of the atrial wall and the ventricular wall,respectively, as shown in FIG. 18 b. The vertical leg 233 v is thusspaced from the heart wall. The horizontal legs 233 h may be secured tothe heart walls by suturing or other suitable, similar attachmentmechanisms. The horizontal portion 231 h of the beam member 231 extendsfrom the vertical leg 233 v and through the atrial wall so as to suspendthe plug member 201 in the appropriate position relative to the mitralvalve MV. The sleeve 232 is positioned on the horizontal portion 231 h,and optionally may be slidable relative thereto, such that the heartwall surrounds the sleeve 232. The sleeve 232 therefore provides asurface that permits ingrowth of the heart wall muscle to assist instabilizing the device relative to the heart. The ingrowth of the heartwall into the sleeve 232 also may prevent damage to the heart wall whichwould otherwise occur as a result of relative motion between the heartwall and the horizontal portion 231 h caused by the heart's beating.

It will be apparent to those skilled in the art that variousmodifications and variations can be made in the devices and relatedmethods for improving mitral valve function of the present invention andin construction of such devices without departing from the scope orspirit of the invention. As an example, a combination of devicesdepicted above may be used for achieving improved mitral valve function.Moreover, although reference has been made to treating the mitral valveand to the bloodflow patterns relating to the mitral valve, it isenvisioned that other heart valves may be treated using the devices andmethods of the present invention. Those having skill in the art wouldrecognize how the devices and methods could be employed and/or modifiedto treat valves other than the mitral valve, taking into considerationfactors such as the desired blood flow patterns through the valve. Otheroptional embodiments of the invention will be apparent to those skilledin the art from consideration of the specification and practice of theinvention disclosed herein. The specification and examples are exemplaryonly, with a true scope and spirit of the invention being indicated bythe following claims.

1. A method for reducing regurgitation of a mitral valve, comprising:providing a mitral valve plug having an elongate member extendingtherefrom, wherein the mitral valve plug is disposed within a catheter;advancing the catheter and the mitral valve plug to an orifice of themitral valve; positioning the mitral valve plug within the orifice ofthe mitral valve, such that leaflets of the mitral valve engage themitral valve plug during a portion of a cardiac cycle; and securing theelongate member to a wall of a heart chamber.
 2. The method of claim 1,wherein an anchor is connected to the elongate member.
 3. The method ofclaim 1, wherein the mitral valve plug includes a coating.
 4. The methodof claim 3, wherein the coating includes an agent configured to promoteendothelial growth.
 5. The method of claim 1, wherein advancing themitral valve plug includes advancing the mitral valve plug through ablood vessel, a right atrium, and a left atrium.
 6. The method of claim1, wherein the mitral valve plug includes a first configuration whendisposed within the catheter.
 7. The method of claim 6, wherein mitralvalve plug changes to a second configuration different from the firstconfiguration when removed from the catheter.